Clan Steel Viper, the instigator of the Wars of Reaving, had already considered bringing the Scorpions before the Grand Council, believing them tainted by the Hellions and by the Eridani Light Horse. The Scorpion Seekers also made contact with pirates and bandits when exploring the Periphery, and their reconnaissance mission to Nueva Castile was carried out with un-Clanlike deception tactics. All of this, according to the Vipers, was enough to Reave the whole of Clan Goliath Scorpion, but the Viper Annihilation gave the Scorpions a brief respite.

While the Scorpions emerged from the Wars of Reaving as the second largest of the Homeworld Clans, the Scorpions failed to translate this strength into a permanent position of power. Instead, their obsession with Star League relics led to their Abjurement from Clan Space altogether. In December 3078 the Scorpions defended Hector against a Clan Cloud Cobra assault. During the fighting at the Bright Ledge genetic research station, one salvo from a Scorpion 'Mech blew the main bridge dropping half of the 73rd Cobra Guards into the ravine; the Cobras declared the remaining Scorpions dezgra and crushed them. Upon claiming them isorla, they discovered that the Scorpion scientists, without authorization from the Khans or the Clan Council, had been experimenting with integrating Eridani Light Horse genes in the Clan legacies. The matter was brought before the Grand Council, and a Trial of Abjuration was immediately approved. Despite this, the Clans moved slowly to carry it out, and this allowed the Scorpions to evacuate much of their assets to Waypoint 531. The forces left behind fought valiantly but were ultimately defeated. The survivors gathered at Waypoint 531, then in early 3080 they moved into and conquered Nueva Castile.

Modeled upon the Ghost Bear-Rasalhague form of integration, the Scorpions soon began merging both Castilians and Umayyads into the Clan caste system. The Scorpions modified it somewhat from Clan norms, adding two new castes.

The majority of the Castilian population ended up in the laborer caste, a status many proud Castilians found difficult to accept. In contrast, few Castilians and Umayyads were assigned to the merchant caste, making it the smallest caste in the Imperio. A large number of Umayyads were accepted into the technician caste, while the scientist caste was swollen with a sizable number of Castilians. Only a very small intake of Castilian and Umayyad officers were accepted into the warrior caste.

The two new castes created by the Scorpions were the support and garrison (or 'grunt') castes. The former included those dealing with supply, administration, emergency services, and such. The garrison caste became the new niche for most of the Castilian and Umayyad soldiers, consisting primarily of infantry and armor forces.[3]

Having been Abjured from Clan society, the Escorpión Imperio has no official relations with any other Clan. Clan Coyote raided Navarre in 3088, inserting a few Watch operatives who spread rumors of the Umayyads' alleged descent from Clan Wolverine; this resulted in a souring of relations between the Umayyads and former Scorpion warriors. By 3095, the Coyotes, Clan Cloud Cobra, and Stone Lions also began passive intelligence operations within the Imperio.[4]